Instructions:
Blacken some cells in the diagram so that in the remaining cells no number occurs more than once per row or column. All unblackened cells must be connected (i.e. the blackened cells may not divide the puzzle into two or more parts). Two blackened cells may not be adjacent, though may touch by a corner.
For a correct solution only the blackened cells are considered.

Instructions:
Enter the numbers as indicated into the diagram so that in every row, every column and every outlined area each number appears exactly once. The small numbers in the cages indicate the sum of the numbers in the cage. No cage may contain duplicate numbers.

Mouse Controls:
The first click in a cell places a 1. Every other click leads to the next number. If you have already reached the maximum number the next click empties the cell.
A click in the bottom left of the cell enables expert mode for this cell. In expert mode, you can toggle each number separately. A second click in the bottom left ends expert mode.

Keyboard Controls:
Number keys: Enter the number into the cell
Space: Delete cell contents
Minus key: Marks number ranges
#: toggle between the expert mode and normal mode.
In expert mode, you can toggle each number separately using the number keys.

Instructions:
Draw a single continuous loop along the gridlines in the diagram.
You do not need to visit all grid points.
The numbers in each cell indicate how many of that cell's edges are used by the path.
The path cannot cross or touch itself.

Instructions:
Insert a digit from 1 to <gridsize> into every cell, so that each digit appears once in each row and column .
Each digit in a cell represents the height of a building.
Numbers outside the grid indicate how many buildings a distant observer could see (at least part of) in that row or column.
A building will hide any shorter buildings behind it.

Mouse Controls:
The first click in a cell places a 1. Subsequent clicks increment the number. After the maximum, the next click empties the cell.
A click in the bottom right of the cell enables expert mode for this cell. In expert mode, you can toggle each number separately. A second click in the bottom left ends expert mode.

Keyboard Controls:
Number keys: Enter the number into the cell
Space: Delete cell contents
Minus key: Marks number ranges
#: toggle between the expert mode and normal mode.
In expert mode, you can toggle each number separately using the number keys.

Instructions:
Complete the puzzle like a crossword, using the digits 1 to 9 instead of letters to create numerical "words".
Clues to the left or top of each word indicates the sum of digits in that word.
Digits may not be used more than once within each word.

Mouse Controls:
The first click in a cell places a 1. Subsequent clicks increment the number.
After the maximum, the next click empties the cell.
A click in the bottom right of the cell enables expert mode for this cell.
In expert mode, you can toggle each number separately.
A second click in the bottom left ends expert mode.

Keyboard Controls:
Number keys: Enter the number into the cell
Space: Delete cell contents
Minus key: Marks number ranges
#: toggle between expert mode and normal mode.
In expert mode, you can toggle each number separately using the number keys.

There seems to be quite a bit of inconsistency between the instructions for selecting and deselecting expert mode (which incidentally seems like a misnomer). Are the applets actually different in how this is implemented or are the instructions mistranslated?

There seems to be quite a bit of inconsistency between the instructions for selecting and deselecting expert mode (which incidentally seems like a misnomer). Are the applets actually different in how this is implemented or are the instructions mistranslated?

Thank-you. 20-30 minutes here and there, and at least 4 of us working on it helps...

Once the initial Anglification is done for all puzzles, I'll go through applying some consistency. The original German text has clearly been written piecemeal in parts, so that lacks consistency too. An example I specifically highlighted was the use of clicking bottom left for entering 'expert' mode in one or two puzzles, whilst nearly all other puzzle types use bottom right for this function.

I'm not sure if it's one applet or many - I suspect one, actually, compiled from multiple mini-applets.

Do you have another term in mind for 'expert mode' ? Checkbox/Checkmark/Detail/Full mode; other?

PuzzleScot wrote:
Once the initial Anglification is done for all puzzles, I'll go through applying some consistency. The original German text has clearly been written piecemeal in parts, so that lacks consistency too. An example I specifically highlighted was the use of clicking bottom left for entering 'expert' mode in one or two puzzles, whilst nearly all other puzzle types use bottom right for this function.

Do you have another term in mind for 'expert mode' ? Checkbox/Checkmark/Detail/Full mode; other?

Croco-puzzle has grown over many years - if you have a look at the old Preisrätsels from 2006 you will notice that quite a few puzzle types have been added since that time (Masyu and Heyawake, for example). The documentation reflects this organic growth...

Expert mode for me means filling in and eliminating candidates for a cell's content. Would a term like candidate mode work for you native speakers, or am I thinking too German there?

Instructions:
Draw a laser ray through the diagram that runs only diagonally. It enters and leaves the diagram in the locations that are indicated by the arrows. Place mirrors in some grid intersections that are hit by the laser ray on one side only.
The numbers at the top and left indicate the number of cells in that row or column through which the ray runs. The numbers at the bottom and right indicate the number of mirror that need to be placed along that grid line. All intersections are given.
For a correct solution you only need to fill in the laser ray, all other information (including incorrectly placed mirrors) is ignored.

Keyboard Controls:
#, *, and Q: laser ray or mirror
-, /, and W: empty cell (marked by a dash) or no mirror (marked by an empty circle)
Space: Delete contents
Escape: Toggle between cell and mirror caret
The laser ray is automatically drawn into the cells in the right direction.

Instructions for spirals:
Enter the numbers as indicated into the diagram so that in every row and every column each number appears exactly once. When following the spiral from the outside to the inside the digit sequence 1, 2, .., N must repeat. N stands for the maximum value.

Instructions for non-spirals:
Enter the numbers as indicated into the diagram so that in every row and every column each number appears exactly once. When walking the labyrinth from the outside to the inside the digit sequence 1, 2, .., N must repeat. N stands for the maximum value.

Mouse Controls:
The first click in a cell places a 1. Every other click increments the number. When the maximum number has been reached the next click places a minus sign (to mark the cell as empty). An additional click clears the cell content.
A click in the lower right corner of the cell starts the expert mode for this cell only. In expert mode, you can toggle each number separately. Clicking again in the lower right corner closes expert mode.

Keyboard Controls:
Number keys: Enter the number into the cell
Minus key: empty cell (marked by a minus sign)
Space: Delete cell contents
#: toggle between the expert mode and normal mode.
In expert mode, you can toggle each number separately using the number keys.

Candidate mode or sledgehammer mode might be better. What I meant was that I doubt if any expert solver would ever consider using this mode. Surely it is too slow and cumbersome, and hampers visualisation of the puzzle.

I know I gave expert mode a spin for the hardest of the Easter Vergleichssudoku puzzles -- not sure how much use it was, but it was good for at least notating "I know the 1 has to be in one of these two squares". More cumbersome to use than the shift-typing on Nikoli though.

As far as discrepancies on commands, I popped open an old Preisraetsel and verified the commands to be sure they worked as described on mine.

You must locate a snake in the grid.
The head and tail of the snake are given. Occasionally some other parts of the snake are also given.
The snake may not touch itself, not even diagonally.
The numbers at the edge of the grid indicate how many segments of the snake are in that row or column.

Instructions:
Complete the diagram with magnetic and neutral (black) tiles.
Each magnetic tile has two poles (+ and -), one on each half.
Two halves with the same poles must not touch horizontally or vertically.
The numbers at the side and top of the diagram indicate how many positive and negative poles appear in that row or column.
If a clue number is blank, you need to deduce the missing value.

Instructions:
Draw pills into the diagram that have the specified values, with every value occurring only once. The pills span three cells, and they can be positioned horizontally or vertically. The value of a pill is the sum of its three cells. The numbers at the edges indicate the sum of all cell contents in that row or column that are part of a pill.
For a correct solution only full size pills are considered. Other marks including partial pills are ignored.

david mcneill wrote:There seems to be quite a bit of inconsistency between the instructions for selecting and deselecting expert mode (which incidentally seems like a misnomer). Are the applets actually different in how this is implemented or are the instructions mistranslated?

This is indeed a little inconsistent. The problem arose with "Gebietssummen" and "Killer": As there is allready a small number in the top left corner, the grid for the expert mode ist much smaller than in all the other types. With small applets, there was no space left at the bottom right. Therefore I moved the dot to the left, where a lot of space remains in this two types.

Instructions:
Enter digits from 1 to 9 into the pyramid cells so that every cell contains either the sum or the difference of the content of the two cells below. Rows that are marked in grey may not contain duplicate digits. Rows that are marked in white must contain at least one duplicate digit.

Mouse Controls:
The first click in a cell places a 1. Every other click leads to the next digit. If you have already reached the last digit, another click empties the cell.
A click in the lower right corner of the cell starts the expert mode for this cell only. In expert mode, you can toggle each digit separately. Clicking again in the lower right corner closes expert mode.

Keyboard Controls:
Number keys: Enter the number into the cell
Space: Delete cell content
#: toggle between expert mode and normal mode. In expert mode you can toggle each digit separately using the number keys.

Instructions:
Draw stars in some of the blank cells, so that every star is pointed to by at least one arrow.
Every arrow points to at least one star. The path of an arrow can pass through other arrows and stars.
The numbers aroung the grid indicate how many stars are located in the corresponding row or column.
For a correct solution, only the fields with a star are relevant.

The first click on a cell containing an arrow marks that cell with a cross. A second click deletes it again.
Alternatively, you can also drag the mouse over several cells - a star is placed in all these fields.

In a cell containing an arrow: #, Q * marks with a cross, and the space bar clears again.

[Additional control hint, not listed in the original German rules: if you hold a keyboard key, and simply move the mouse over a series of cells, all those cells take the value of the key being held down. This probably applies to other puzzle types too, but is not tested.]